Nia Vardalos didn't enter motherhood with ease. This Canadian-born, Second City-trained actress and author (most well known for writing and starring in the movie "My Big Fat Greek Wedding,") pulls back the curtain on her struggles to become a mom in her new book, "Instant Mom" (Harper One).

"We're all instant moms — no matter how your child has come to you, no one is ever prepared for this daunting responsibility of keeping a child alive," she said.

Vardalos adopted a daughter in 2008 with her husband, actor Ian Gomez, after a decade of trying to become a mom.

"We struggled with fertility treatments and then we had so many 'almosts' with the adoption process and it was heartbreaking," she said. "When we were finally matched with a 3-year-old girl who was in foster care I realized all of those mis-steps that didn't work out — they were meant to not happen. I would do it all again because every single thing that didn't work led me to this incredible little girl. "

Daughter Ilaria is now a "thriving" 7-year-old.

"Every day there's a new discovery," Vardalos said. "She was telling a story in the kitchen the other day about how she was going to kiss a boy but there's a 'no-kissing' policy in school and she was so funny about it and I just looked at her thinking, 'I can't believe how she's grown up into this amazing little person.'"

In honor of Mother's Day, here are some lessons Vardalos has learned through the process of becoming a mom:

Support other moms.

"I met mothers on the playground of other 3-year-olds who looked well-groomed and rested and I looked like I was homeless because I was trying to negotiate with a child I didn't know and feed her and bathe her. And they came over and talked to me and recognized the dazed and confused look in my eyes that they themselves had when they had an infant. We became friends, and that was huge because they said, 'I've been there.' You need to have that sense of community."

Don't take it personally.

Vardalos said if our children lash out, it could have nothing to do with us.

"When my daughter would have trouble sleeping and she would cry and panic, and coming from foster care, she was so used to having people come and go," she said. "So I couldn't take this behavior personally. Just remembering this really helped me. She was in survival mode and thinking 'don't leave me.' That was really enlightening for me."

Empower your child.

"Now that she's almost 8, I let Ilaria make her own choices," she said. "For example, with food, I'm trying to give her the gift of organization and to process and so she fills her own backpack. I will make lunch for her, but I really say 'Listen to your body.' So if she says, 'I want chocolate,' and I say, 'Sure,' because she will have one bite of it and then she's done. If I withhold it then she would want more and overindulge."

Be fearless.

"When I am happiest is when I'm being a fearless idiot. I'm not talking about being reckless, like jumping out of an airplane without a parachute. It's about saying 'I'm going to parachute.' I'm very happy right now because I challenge myself in that I wrote from a place of 'This is how I feel. I don't care what you think,' and that's really rare for me. And the stories people are sharing with me since I've talked about my struggles are amazing. It's opened a dialogue about being fallible and saying 'Just because I can't have my own child, doesn't mean I've failed.'"